This Element is an opinionated introduction to Heidegger's phenomenology in Being and Time and surrounding works, framed in terms of Heidegger's debts to and divergence from Husserl's phenomenology. Section 1 situates Heidegger's and Husserl's phenomenology with respect to the 'identity-crisis of philosophy,' in particular the debate over whether philosophy is a science or a mere cataloguing of worldviews. Section 2 critically evaluates Heidegger's claims that various forms of conscious intentionality central to Husserl's phenomenology are 'derivative' or 'founded.' Section 3 turns to method, exploring whether Heidegger adopts Husserl's reductions, platonism, and method of essential seeing and imaginative variation. Section 4 explores Heidegger's hermeneutical turn in phenomenology and explains the uses to which he puts religious sources, mythology, and ordinary language.